/*
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 *
 * This software is open source.
 * See the bottom of this file for the licence.
 */

package org.dom4j.xpath;

import java.util.ArrayList;

import org.dom4j.InvalidXPathException;
import org.dom4j.Node;
import org.dom4j.XPathException;

import org.jaxen.Context;
import org.jaxen.ContextSupport;
import org.jaxen.JaxenException;
import org.jaxen.SimpleNamespaceContext;
import org.jaxen.SimpleVariableContext;
import org.jaxen.VariableContext;
import org.jaxen.XPathFunctionContext;
import org.jaxen.dom4j.DocumentNavigator;
import org.jaxen.pattern.Pattern;
import org.jaxen.pattern.PatternParser;
import org.jaxen.saxpath.SAXPathException;

/**
 * <p> <code>XPathPattern</code> is an implementation of Pattern which uses an
 * XPath xpath. </p>
 * 
 * @author <a href="mailto:jstrachan@apache.org">James Strachan </a>
 * @version $Revision: 1.2 $
 */
public class XPathPattern implements org.dom4j.rule.Pattern
{
   private String text;

   private Pattern pattern;

   private Context context;

   public XPathPattern(Pattern pattern)
   {
      this.pattern = pattern;
      this.text = pattern.getText();
      this.context = new Context(getContextSupport());
   }

   public XPathPattern(String text)
   {
      this.text = text;
      this.context = new Context(getContextSupport());

      try
      {
         this.pattern = PatternParser.parse(text);
      }
      catch(SAXPathException e)
      {
         throw new InvalidXPathException(text, e.getMessage());
      }
      catch(Throwable t)
      {
         throw new InvalidXPathException(text, t);
      }
   }

   public boolean matches(Node node)
   {
      try
      {
         ArrayList list = new ArrayList(1);
         list.add(node);
         context.setNodeSet(list);

         return pattern.matches(node, context);
      }
      catch(JaxenException e)
      {
         handleJaxenException(e);

         return false;
      }
   }

   public String getText()
   {
      return text;
   }

   public double getPriority()
   {
      return pattern.getPriority();
   }

   public org.dom4j.rule.Pattern[] getUnionPatterns()
   {
      Pattern[] patterns = pattern.getUnionPatterns();

      if(patterns != null)
      {
         int size = patterns.length;
         XPathPattern[] answer = new XPathPattern[size];

         for(int i = 0; i < size; i++)
         {
            answer[i] = new XPathPattern(patterns[i]);
         }

         return answer;
      }

      return null;
   }

   public short getMatchType()
   {
      return pattern.getMatchType();
   }

   public String getMatchesNodeName()
   {
      return pattern.getMatchesNodeName();
   }

   public void setVariableContext(VariableContext variableContext)
   {
      context.getContextSupport().setVariableContext(variableContext);
   }

   public String toString()
   {
      return "[XPathPattern: text: " + text + " Pattern: " + pattern + "]";
   }

   protected ContextSupport getContextSupport()
   {
      return new ContextSupport(new SimpleNamespaceContext(),
         XPathFunctionContext.getInstance(), new SimpleVariableContext(),
         DocumentNavigator.getInstance());
   }

   protected void handleJaxenException(JaxenException exception)
      throws XPathException
   {
      throw new XPathException(text, exception);
   }
}

/*
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided that the
 * following conditions are met:
 * 
 * 1. Redistributions of source code must retain copyright statements and
 * notices. Redistributions must also contain a copy of this document.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 * 
 * 3. The name "DOM4J" must not be used to endorse or promote products derived
 * from this Software without prior written permission of MetaStuff, Ltd. For
 * written permission, please contact dom4j-info@metastuff.com.
 * 
 * 4. Products derived from this Software may not be called "DOM4J" nor may
 * "DOM4J" appear in their names without prior written permission of MetaStuff,
 * Ltd. DOM4J is a registered trademark of MetaStuff, Ltd.
 * 
 * 5. Due credit should be given to the DOM4J Project - http://www.dom4j.org
 * 
 * THIS SOFTWARE IS PROVIDED BY METASTUFF, LTD. AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL METASTUFF, LTD. OR ITS CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Copyright 2001-2005 (C) MetaStuff, Ltd. All Rights Reserved.
 */
